document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1000791>Question 1000791</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am taking a trigonometry class right now and one of the equations I need help solving is: \r<BR>\n" );
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document.write( "2sin^2x+3sinx+1=0 \r<BR>\n" );
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document.write( "From this equation I am required to use the quadratic formula, solve for all possible values of \"x\" and then find what angles \"x\" is on the unit circle. \r<BR>\n" );
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document.write( "I really am not sure how to solve this, I need some help. Thanks!  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #618137 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52800)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=618137\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Hello,\r<BR>\n" );
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document.write( "introduce the new variable &nbsp;y = sin(x). &nbsp;You will get a quadratic equation for &nbsp;y\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2y%5E2+%2B+3y+%2B+1 ALIGN=MIDDLE  ALT=\"2y%5E2+%2B+3y+%2B+1\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0 ALIGN=MIDDLE  ALT=\"0\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Solve it and find &nbsp;y: &nbsp;&nbsp;y = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-1%2F2 ALIGN=MIDDLE  ALT=\"-1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;and &nbsp;y = -1.\r<BR>\n" );
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document.write( "Then determine x:\r<BR>\n" );
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document.write( "Case 1: &nbsp;&nbsp;y = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-1%2F2 ALIGN=MIDDLE  ALT=\"-1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;&nbsp;---> &nbsp;&nbsp;sin(x) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-1%2F2 ALIGN=MIDDLE  ALT=\"-1%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;&nbsp;---> &nbsp;&nbsp;x = 210° + k*360° &nbsp;and &nbsp;x = 330° + k*360°.\r<BR>\n" );
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document.write( "Case 2: &nbsp;&nbsp;y = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-1 ALIGN=MIDDLE  ALT=\"-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;&nbsp;---> &nbsp;&nbsp;sin(x) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-1 ALIGN=MIDDLE  ALT=\"-1\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;&nbsp;---> &nbsp;&nbsp;x = 270° + k*360°\r<BR>\n" );
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document.write( "It is the standard way of solving non-linear equations.\r<BR>\n" );
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